Researchers from the Shanghai Institute of Applied Physics at the Chinese Academy of Sciences have developed a graphene-based nanosheet paper with an inherent ability to fight disease-causing bacteria. According to the researchers, the paper may have applications in antibacterial bandages, shoes that fight foot odor and food packaging.

According to the article, published in the American Chemical Society journal ACS Nano, scientists in the UK discovered graphene in 2004 and since then, researchers have been working on commercial applications for the material. The report explains that graphene is a monolayer of carbon atoms tightly packed into a two-dimensional crystal.

These paper nanosheets were developed from two water-dispersible graphene derivatives, graphene oxide (GO) nanosheets and reduced graphene oxide (rGO) nanosheets, on which bacteria was unable to grow. Graphene-based nanomaterials are said to effectively inhibit the growth of E. coli bacteria. The researchers evaluated this antibacterial activity by investigating the interaction of E. coli DH5α cells with the nanosheets. The metabolic activity of E. coli DH5α cells in the presence of GO nanosheets was measured via a luciferase-based ATP assay kit. After 2 hr incubation with GO nanosheets of 20 μg/mL at 37°C, the cell metabolic activity for E. coli deceased to 70% and to 13% at a GO nanosheet concentration of 85 μg/mL, suggesting a strong antibacterial action.

GO nanosheets were found by the researchers to be biocompatible nanomaterials with mild cytotoxicity. The cytotoxicity of rGO nanosheets is higher than that of GO nanosheets, which could be the result of different surface charges and functional groups of GO and rGO nanosheet surfaces

The research demonstrated that macroscopic freestanding GO and rGO paper can be fabricated from their suspension with simple vacuum filtration. According to the researchers, the graphene oxide sheets can be mass-produced and easily processed to make freestanding and flexible paper with low cost. The researchers expect to find more applications for the sheets, and perhaps their research or research by others may result in an application for foot fungus, nail fungus or other topical applications.